Governments and global health authorities are struggling to halt an outbreak of deadly Ebola virus that has killed at least 3,300 people since it began in West Africa in March. LATEST STORIES > Four close to US Ebola patient quarantined in Dallas apartment > American cameraman for NBC News diagnosed with Ebola in Liberia > EXCLUSIVE-U.S. nears solution for safe disposal of Ebola waste > Liberia says may prosecute man who flew to U.S. with Ebola > Ebola arrival sha